1916] 
ZELLER—PHYSIOLOGY OF LENZITES SAEPIARIA 479 
age reduction in weight due to fungous decay. This may be 
due to different proportions of lignifieation in the different 
samples, or more likely, since other substances like coniferin, 
hadromal, and possibly vanillin are utilized by the fungus, the 
total reduetion would not necessarily bear any defmite rela- 
tion to the reduction of any one of the complex. Helbig (711) 
has made similar cellulose determinations on wood which had 
been altered by Thelephora perdix. This fungus produces a 
white rot, and Helbig found that with the advance of decay 
the percentage of cellulose increases perceptibly. 
Hemicellulase.—The hemicelluloses differ from the true 
celluloses in that they are more easily hydrolyzed, are readily 
dissolved in hot dilute acids, and sometimes give a blue color 
with iodine. Their chemical compositions are determined by 
the products of their hydrolysis. They may yield dextrose, 
mannose, galactose, or mixtures of these, and at times xylose 
or arabinose. According to these decomposition products, 
they are differentiated into dextrans, mannans, galactans, 
mannogalactans, ete. Very frequently hemicelluloses are de- 
posited upon, or as a part of, cell walls, and here play the róle 
of reserve foods, especially in seeds. 
Newcombe (799) determined that the cellulose-hydrolyzing 
enzyme is distinct from other earbohydrases. Schellenberg 
(208), through experiments on numerous fungi, also proved 
that pure eultures grown on substrates containing hemicellu- 
loses and true celluloses would hydrolyze hemicelluloses but 
not the true celluloses. He also shows that the moulds act 
selectively toward the hemicelluloses from various sources. 
He thus differentiates between the different hemicellulases 
which act on various hemicelluloses, and the cellulase which 
hydrolyzes the true cellulose. 
To ascertain whether the enzyme dispersions from mycelium 
and sporophores are active as hemicellulose-hydrolyzers, the 
endosperm of the date seed (Phoenix dactylifera) was used as 
a substrate. 
Date seeds were scraped to remove the outer coats, and then 
were thoroughly washed with sand and soap to remove all 
reducing sugars possible. The seeds were then rinsed in dis- 
